improve suggestion when server-forever is unable to use the port

scopes/harmony/bit/server-forever.ts

@@ -9,6 +9,7 @@
 
 import net from 'net';
 import crypto from 'crypto';
+import { execSync } from 'child_process';
 import { spawn } from '@lydell/node-pty';
 
 export function spawnPTY() {
@@ -79,15 +80,18 @@ export function spawnPTY() {
 
   server.on('error', (err: any) => {
     if (err.code === 'EADDRINUSE') {
-      console.error(`Error: Port ${PORT} is already in use.`);
-      console.error(`This port is assigned based on the workspace path: '${process.cwd()}'`);
-      console.error(`This means another instance may already be running in this workspace.`);
-      console.error(`\nTo resolve this issue:`);
-      console.error(`- If another instance is running, please stop it before starting a new one.`);
-      console.error(`- If no other instance is running, the port may be occupied by another application.`);
-      console.error(
-        `  You can override the default port by setting the 'BIT_CLI_SERVER_SOCKET_PORT' environment variable.`
-      );
+      const pid = getPidByPort(PORT);
+      const usedByPid = pid ? ` (used by PID ${pid})` : '';
+      const killCmd = pid ? `\nAlternatively, you can kill the process by running "kill ${pid}".` : '';
+      console.error(`Error: Port ${PORT} is already in use${usedByPid}.
+This port is assigned based on the workspace path: '${process.cwd()}'
+This means another instance may already be running in this workspace.
+\nTo resolve this issue:
+- If another instance is running, please stop it before starting a new one.
+  If a vscode is open on this workspace, it might be running the server. Close it.${killCmd}
+- If no other instance is running, the port may be occupied by another application.
+  You can override the default port by setting the 'BIT_CLI_SERVER_SOCKET_PORT' environment variable.
+`);
       process.exit(1); // Exit the process with an error code
     } else {
       console.error('Server encountered an error:', err);
@@ -140,3 +144,44 @@ export function getPortFromPath(path: string): number {
 
   return port;
 }
+
+function getPidByPort(port: number): string | null {
+  const platform = process.platform;
+  try {
+    if (platform === 'darwin' || platform === 'linux') {
+      // For macOS and Linux
+      const cmd = `lsof -iTCP:${port} -sTCP:LISTEN -n -P`;
+      const stdout = execSync(cmd).toString();
+      const lines = stdout.trim().split('\n');
+
+      if (lines.length > 1) {
+        // Skip the header line and parse the first result
+        const columns = lines[1].split(/\s+/);
+        const pid = columns[1];
+        return pid;
+      }
+    } else if (platform === 'win32') {
+      // For Windows
+      const cmd = `netstat -ano -p tcp`;
+      const stdout = execSync(cmd).toString();
+      const lines = stdout.trim().split('\n');
+
+      for (const line of lines) {
+        if (line.trim().startsWith('TCP')) {
+          const columns = line.trim().split(/\s+/);
+          const localAddress = columns[1];
+          const pid = columns[4];
+
+          if (localAddress.endsWith(`:${port}`)) {
+            return pid;
+          }
+        }
+      }
+    } else {
+      console.error('Unsupported platform:', platform);
+    }
+  } catch (error: any) {
+    console.error('Error executing command:', error.message);
+  }
+  return null;
+}